Active participation in the medical consultation has been demonstrated to benefit aspects of patients' subsequent psychological well-being. We investigated two interventions promoting patient question-asking behaviour. The first was a question prompt sheet provided before the consultation, which was endorsed and worked through by the clinician. The second was a face to face coaching session exploring the benefits of, and barriers to, question-asking, followed by coaching in question-asking behaviour employing rehearsal techniques. Sixty patients with heterogeneous cancers, seeing two medical oncologists for the first time, were randomly assigned to one of three groups: two intervention groups and one control group. Sociodemographic variables and anxiety were assessed prior to the intervention which preceded the consultation. The consultations were audiotaped and subsequently analysed for question-asking behaviour. Anxiety was assessed again immediately following the consultation. Questionnaires to assess patient satisfaction, anxiety and psychological adjustment were sent by mail 2 weeks following the consultation. Presentation and discussion of the prompt sheet significantly increased the total number of questions asked and the number of questions asked regarding tests and treatment. Coaching did not add significantly to the effects of the prompt sheet. Psychological outcomes were not different among the groups. We conclude that a question prompt sheet addressed by the doctor is a simple, inexpensive and effective means of promoting patient question asking in the cancer consultation.